Differential Phenotype of Primary Bilateral Macronodular Adrenal Hyperplasia and Other Bilateral Adrenal Lesions With Associated Subclinical Hypercortisolism. Study of 98 Patients.

Abstract

Purpose: To evaluate the prevalence of primary bilateral macronodular adrenal hyperplasia (PBMAH) in patients with adrenal incidentalomas (AIs) with subclinical hypercortisolism. Also to analyse the differential phenotype of patients with PBMAH compared to other bilateral adrenal lesions which do not meet PBMAH definition.Methods: Retrospective study of patients with AIs diagnosed in our centre between 2013 and 2019 (n=730). Patients with bilateral disease and associated subclinical hypercortisolism (possible ACS or ACS) were included (n=98). Possible ACS and ACS were defined as a cortisol post-1mg-dexamethasone suppression test (DST)>1.8µg/dl but ≤5.0µg/dl and >5.0µg/dl. without specific clinical signs of Cushing´s syndrome, respectively. PBMAH diagnosis was established in patients with subclinical hypercortisolism, hyperplasia and bilateral adrenal nodules >1cm.Results: PBMAH was confirmed in 31.6% of bilateral AIs with subclinical hypercortisolism. Patients with PBMAH presented a higher prevalence of ACS than non-PBMHA (OR 4.1, 95%CI 1.38-12.09, P=0.010), but differences disappeared after adjusting by tumour size and total adenomatous mass (adjusted OR 2.3, 95%CI=0.65-8.27 and 2.3, 95%CI 0.47-11.21, respectively). However, no significant differences in the cardiometabolic profile of both groups were observed. Tumour size and total adenomatous mass were significantly higher in PBMAH (30.2±12.16 vs 24.3±8.47, P=0.010 and 53.9±20.8 vs 43.3±14.62, P=0.023).Conclusion: PBMAH is common in patients with incidentally detected bilateral adrenals lesions with associated subclinical hypercortisolism. The higher prevalence of ACS in PBMAH compared to non-PBMAH is associated with a higher tumour size and total adenomatous mass in PBMHA, but no differences in the cardiometabolic profile were observed between both groups.